The effects of 16 psychotropic drugs on food intake and body weight were studied in female Wistar rats under carefully controlled conditions. After 3 days of placebo treatment the drugs were administered orally 1 hr prior to a 12-hours-per-day feeding period for at least 3 further days. Normal daily feed consumption averaged 6.11 g/100 g BW. Haloperidol, reserpine, chlorpromazine, chlorprothixene, promethazine, azacyclonol, imipramine, and amitriptyline in appropriate doses all reduced both food intake and body weight, but there were marked differences in activity. Small amounts of chlorpromazine may even stimulate feeding behaviour. Chlorpromazine sulfoxide was without influence. The central stimulant Tradon® evoked anorexia whereas only short-lasting anorexigenic effects if any were observed following the administration of either 2-diethylamino-4-oxo-5-phenyl-oxazoline or pipradol. On the other hand chlordiazepoxide, phenobarbital, and to some extent oxazepam caused the animals to increase their feed consumption and to gain weight. The results are discussed with regard to clinical reports of appetite and weight changes due to psychotropic drugs.